Hydraulic press



T. F. STACY HYDRAULIC PRESS Sept; 3, 1935.

2 Sheets-Sheet 1 Filed Jan. 25, 1934 STEAMTRAP W 2 v 4 f i M X A L a h w 7 W a w? -W- @Z a fi H w .J 1 4 MW J W W, i. W {a W f fig v, WW I Sept. 3, 1935. T1; T Y I 2,013,587 7 HYDRAULIC PRESS Filed Jan. 25, 1934 2 Sheets-Sheet 2 WVZWZWE 2%, M

I y 417mm Patented Sept. 3, 1935 UlTE STATS HYDRAULIC PRESS Ohio Application January 25, 1934, Serial No. 708,276

9 Claims.

This invention relates to hydraulic presses or the like, and particularly to presses which may be advantageously used with hot press plates such as in the molding and curing of articles made of 5 synthetic resins.

An object of the invention is to improve the construction of hydraulic presses and the like, with which the frame may have a maximum strength and rigidity with a minimum of size and weight, and which will undergo a minimum of distortion in a press-operation.

Another object of the invention is to provide an improved hydraulic press of the hot plate type in which the loss of heat through radiation may be reduced materially, and with which articles to be pressed may be easily and conveniently inserted in and removed from the press.

Another object of the invention is to provide an improved hydraulic press for accomplishing any or all of the above objects and which will be relatively simple, inexpensive and practical.

Various other objects and advantages will be apparent from the following description of an embodiment of the invention, and the novel features will be particularly pointed out hereinafter in connection with the appended claims.

In the accompanying drawings:

Fig. 1 is a front elevation of a hydraulic press of the hot plate type, which is constructed in accordance with this invention, a portion of the outside shield of the front face of the press being partly broken away at one corner to show certain details of construction.

Fig. 2 is a side elevation of the same;

Fig. 3 is a plan of the same;

Fig. 4 is an enlarged plan of one corner of the press to show certain details of construction;

Fig. 5 is a sectional elevation of a portion of the press, the section being taken approximately along the line 55 of Fig. 1;

Fig. 6 is a transverse sectional elevation through the central portion of the press, the section being taken approximately along the line 65 of Fig. 2; and

Fig. 7 is a transverse central sectional elevation through the upper portion of the press, the section being taken approximately along the line 'l-l of Fig. l and illustrating the door or shiftable section of the shield across one face of the press open, and the similar section or door at the other face closed.

In the illustrated embodiment of the invention, and referring particularly to Figs. 1 to 6, the press includes a pair of side plates in which are disposed in parallel, face to face relation, but spaced somewhat apart. An upper head member ii and a lower head member ii are disposed between the side plates l adjacent the upper and lower portions of those side plates, so as to form with the side plates a press frame i which is generally rectangular in shape and with its front and rear faces open. Both the side plates and head members are relatively thick, and the head members are preferably thicker than the side plates.

The upper head member H is provided, along its lower face and at its side walls abutting the side plates ID, with tongues, or flanges is which have a substantial width, measured vertically and beginning approximately at the lower face of that head member. These tongues or flanges 53 run continuously from front face to rear face of the frame and are, therefore, approximately coextensive in length with the width of the side walls of that head member which abuts the side plates It. The plates it are provided with slots or grooves [4 which extend transversely thereof from front face to rear face of the frame at a substantial distance below the upper end edges of the plates.

These grooves I4 snugly receive or fit over the flanges or tongues E3 on the upper head member, so as to provide an interfitting tongue and groove connection between the upper head member and the sideplates. The side plates extend at least to substantially the upper face of the upper head member, and threaded studs or screws i pass through suitable passages or apertures in the side plates If] at points closely adjacent the upper end edges of the plates and are threaded into the upper head member, as shown clearly in Fig- 6, so as to tie the side plates It] firmly'to the upper head member. These threaded studs or screws l5 are arranged in a row across the side plates In, as shown in the Fig. 2, and are placed as far as is possible above the interfitting tongue and groove connection between the side plate and upper head member, for a purpose which will appear presently.

Similarly, the lower head member i2 is pro-- vided along its side edges abutting the side plates, and closely adjacent the upper face of that head member, with flanges or tongues it, which are fitted into slots il in the abutting faces of the side plates, so as to provide interfitting tongue and groove connections between the side plates and the lower head member which are similar to the tongue and groove connections between the upper head member and the side plates. The side plates i0 depend below the tongues or flanges i6 and along opposite sides of the lower head member i2 for a substantial distance which is preferably at least equal to the distance from the upper face of the head member Ii to the tongues l3 of the upper head member.

A plurality of threaded studs or screws it? are passed through the lower ends of the side plates H3 at points closely adjacent their lowermost edges, and are threaded intothe abutting portions of the lower head member 12 so as to tie the side plates firmly to the lower head member 12. The studs or screws l8 are arranged in rows across the lower portions of the plates l and are disposed as far as possible below the flanges or tongues I6.

By disposing the screws or studs l and I8 as far as possible from the flanges or tongues I3 and I6 respectively, a frame construction is pro-- vided which has maximum rigidity and strength during a pressing operation. For example, when forces are applied to the head members tending to separate them vertically, there will be not only shearing forces at the tongue and groove connections between the head members and side plates, but also shearing forces on the studs or screws [5 and H3. In addition, the side plates, because of the slots l4 and I! therein, will be subjected to stresses tending to flex the upper and lower ends outwardly about the tongue and groove connections, and the bending moments so set up at the tongue and groove connections will be resisted or opposed by the counter-bending moments exerted on the upper and lower ends of the side plates by studs l5 and [8, respectively.

The greater the distance of the studs l5 and I8 from the adjacent tongue and groove connections between the head members and the side plates, the greater will be, the bending moments which they can exert on the side plates in opposition to the forces tending to flex the side plates, about the tongue and groove connections of the head members and side plates as fulcrums. By placing the tongues I3 and I6 closely adjacent the lower face of the upper head member and the upper face of the lower head member respectively, it is possible to have the studs and IS a very substantial distance from the related or adjacent tongue and groove connections, without unnecessarily increasing the thickness of the upper and lower head members above that necessary to carry the pressing stresses.

The lower head member is provided with a depending boss i2a having therein a cavity or welllike chamber 49 opening upwardly through the upper face of said member, and this cavity serves as the operating chamber or cylinder of a hydraulic ram. A piston of this ram reciprocates vertically in this well or chamber 19, and at its upper end which extends above the upper face of the lower head member l2, it is attached to the underside of a platen 2! that extends between the side plates l0 and from the front to the rear face of the frame. When the ram piston 20 is shifted upwardly by pressrue in the chamber IS, the platen 2| will be carried upwardly toward the upper head member II. A fluid under pressure may be admitted to the chamber I9 by means of a pipe 22 leading from a controlled source (not shown) of a pressure operating fluid. A packing gland 23 may be provided at the open end of the chamber IQ for cooperation with the piston 23 to prevent leakage of the operating fluid from the chamber IS. The boss may be provided with a flange 24 at its lower end which serves as a support or base for the press.

When the press is to be used for the pressing of articles while subjected to heat, hot press plates 25 and 2B are secured to the under face of the upper head member H and the upper face of the platen 2| respectively. These hot plates may be heated in any suitable manner, but by way of example are shown as the type heated by a fluid such as steam which is circulated through suitable passages in the hot plates. Such hot plates are disclosed and claimed in U. S. patent to Polley, 1,929,824, issued October 10, 1933 to which reference may be had for a more complete disclosure of the details of such plates that may be advantageously used in connection with a press of this type.

In order to increase the capacity of the press it is also possible to provide one or more additional hot, intermediate press plates or platens 21 which are disposed between the press plates 25 and 26, but for the purpose of illustration, only one of these plates 21 is illustrated. This intermediate plate 21 is of a size corresponding to the plates 25 and 26, and it is disposed in the frame between the side plates It). This plate 21 is provided at both its front and rear edges with tongues or arms 28 which extend or project over the side edges of the plates H], as shown particularly in Figs. 1 and 4.

Suitable stop pins or studs 29 are provided on the side edges of the side plates Ill below the projecting tongues or arms 28, so as to support thereby the intermediate plates 2? in a normal or retracted position, such as shown in the drawings, in which it is approximately midway between the press plates 25 and 26. When the platen 29 is operated upwardly, its press plate 26, after some idle movement, will engage the plate 21 and shift it upwardly towards the upper plate 25, but when the platen 21 is lowered the intermediate plate 21 will descend with it until it reaches the stops 29, and then the plate 2i will descend without it into the position shown in the drawings.

The heating medium, such as steam, may be supplied to the hot press plates 25, 26 and 2? in all their relative positions in any suitable manner, but in the illustrated embodiment of the invention steam is supplied by a pipe 30 to the upper press plate 25 at one side thereof and is removed form the opposite side of that press plate, with any water of condensation, through a pipe 3!. The pipe 3i, at its outer end is connected by a hinged or swivel joint to an angularly disposed, tubular arm or pipe 32 with which it communicates, and this pipe 32 is swiveled to and communicates with a similar pipe arm 33, which in turn is swiveled to and communicates with a pipe 34 that projects from one side 0 the intermediate plate 21.

Steam leaving the upper plate 25 passes through the pipes 3|, 32, 33 and 34 into the passages of the intermediate plate 2?, throughout all vertical movements of the plate 2?, by reason of the swivel connections between these connecting pipes. Steam and water of condensation are removed from the passages of the plate 27 by a pipe 35 which may, for convenience, extend from the plate 21 at the side opposite the connection to the pipe 34, and this pipe 35 is swiveled to and communicates with one end of an angularly disposed pipe or tubular arm 36.

The other end of this pipe or arm 36 is connected by a swivel joint 31 to one end of a tubular arm or pipe 38 which is similar to the arm 36, and the other end of this arm 38 is connected by a swivel joint 39 to a pipe 40 which extends outwardly from the lower press plate 26. Water of condensation and steam from the plate 2'! are conducted by the pipes 35, 36, 38 and 40 to the passages of the lower press plate 26 throughout all the relative vertical movements of the press plates 26 and 21.

Water of condensation is removed from the passages of the lower press plate 26 by a pipe 4! which, for convenience, may extend from the side of the press plate 26 which is opposite from the connection to the pipe 40, and the outer end of this pipe 4| is swiveled to and communicates with an angularly disposed tubular arm or pipe 42, which in turn is swiveled to one end of another tubular arm or pipe 43. This arm or pipe 43 is also swiveled to a pipe 44 which leads to a hollow casing 45 that is carried by a stud 46 projecting outwardly from one of the side plates I0.

A pipe 4! depends from this tubular casing 45 and communicates with a suitable steam trap. The water of condensation from the press plates thus drains downwardly by gravity from one press plate to another, and is drained from the lowermost press plate through the pipes 4|, 42, 43, 44, casing 45 and pipe 47 to the steam trap, and thus live steam will, at all times, be supplied to all the passages of all the press plates 25, 26 and 21. The swivel joints between the pipes connecting the different press plates permit of the relative, vertical, free movements of the press plates 26 and 2'! without interrupting the steam connections beween all the press plates.

The pipe connections to the press plates are advantageously made at the ends adjacent the side plates I9, and I have found that these pipes 39, 3|, 34 and 35, 40 and 4| preferably extend through vertically elongated slots 48 provided in the side plates l9, and extending from the lower face of the upper head member I l approximately to the upper face of the platen 2| when the platen is in its lowermost or retracted position, as shown particularly in Fig. 6. With these pipes extending from the sides of the press in this manner, they will not interfere materially with access to the press plates from either face of the press or rectangular frame.

It will be noted that the intermediate press plate 21 divides the space between the platen and the upper head member into two pressing compartments or chambers A and B, and in use the articles to be molded are disposed in the chamber A on the press plate 21 and in the chamber B upon the press plate 26. When the platen 2| is elevated, the articles in the chambers A and B will be compressed between the hot plates and molded. In order to increase the efiiciency of this press I propose to provide suitable shields or curtains for the open front and rear faces of this press. For this purpose the front face of the press is covered by a shield 49.

This shield may be a plate extending across the front of the frame, as shown in Figs. 1, 2, 3, 4, 5 and 7 and at its opposite sides or vertical edges is bent angularly to form flanges 59 which telescope over the outer faces of the side plates l6 (Figs. 2, 3 and 4) These flanges 50 are connected to the side plates l9 in any suitable manner, such as by screws 51. An angular member or strip 52 is also clamped under each flange 50 as shown in Fig. 4 and the free angular arm of each strip 52 extends parallel to, but is slightly spaced from, the face of the shield 49 as it extends across the front of the frame, so as to provide a guide or trackway 53 for a movable section, door or closure 54 of the shield 49.

This shield 49 has an imperforate area that permanently closes the front face of the upper chamber A and is cut away along its lower edge to form a door opening 55 through which access may be had to the lower chamber B from the front of the press. The movable section 54 of this shield extends across this door opening 55 and is slidingly mounted and guided by the guideway 53 provided along each side of the shield. This movable section or closure 54 moves upwardly behind the uncut portion of the shield into the position shown in Figs. 1 to 5 and 7, when access to the chamber B is desired.

A spring latch 56 is provided on the movable section or closure 54, adjacent its lower edge and extending upwardly therefrom, and at its free end this latch is provided with a curved or camlike nose 51 which snaps over a stationary, struckout catch or lug 58 provided in the uncut portion of the shield 49 adjacent the upper edge of the cut out door opening 55. When this spring latch 56 is engaged over the lug 58 the door or movable section 54 will be releasably held in its elevated position behind the uncut portion of the shield 49, so that free access may be had from the front of the press to the chamber B. The door or movable section 54, when released, will descend by gravity into its lowermost position in which it closes the opening 55 and prevents access to the chamber B.

A rod 59 extending between and connecting two metal ears 69 on the lower edge portion of the door or movable section 54, provides a convenient handle by which an operator may raise or lower the door or movable section 54. A somewhat similar screen or shield 6| is provided for the rear face of the frame and is similar to the shield or screen 49 except that the door opening 62, instead of being at the lower edge thereof as In the shield 49, is in the intermediate vertical section or zone in alignment with the chamber A, so as to provide for access, from the rear of the press to the chamber A.

The shield 6i is attached to the press frame in the same manner as explained for the shield 49, and the movable door or section 63 which closes the door opening 62 rises behind the uncut upper portion of the shield when it is moved to uncover the door opening 62. This door 63 is shown in closed position in Fig. 7, and in open position in Fig. 2. This door 63 is also provided with a handle 64 which is similar to the handle provided by the ears on flanges and rod 59 for the front closure of the press.

The door 63 is also provided with a spring latch 55 which is similar to the latch 56, and which is adapted to engage with a struck out lug or catch 66, disposed adjacent the upper edge of the door opening 62, in the same manner that the latch 56 engages with the lug 58 for the other door or movable section. In order to aid in guiding the doors or movable sections vertically without binding, I may provide a vertical strip 61, Figs. 3, 4, 5 along each side of the inner face of the doors 54 and 63, and each strip abuts against the free edge of the vertical strips 52 and prevents skewing and binding of the door in its guide-way.

In order to facilitate the work of introducing or removing objects to be pressed from the press chambers A and B I may provide a shelf 68 in front of the press at an approximate level with the upper face of the plate 26 when the platen 2| is in its retracted or lowermost position, and this shelf may be supported at its forward edge by suitable braces 69. Similarly a shelf 19 may be supported at the rear face of the press frame at the level approximately the same as the upper face of the intermediate plate 21, and this shelf 19 is supported at its outer end by braces H. The shelf 58 therefore materially aids in the introduction of objects into the compartment B or their removal therefrom, and the shelf 19 aids in the introduction of objects into the compartment A or their removal therefrom.

In the operation of a press such as that illustrated, steam is admitted to the hot plates 25, 2t and 2? by connecting the pipe 39 to a suitable steam supply or source. The objects to be pressed are inserted into the chambers A and B and the operating fluid under pressure then admitted to the cylinder 19. The attendants at the front and rear of the press, after the objects are inserted into the chambers A and B, close the doors E l and 63 and thus the heat is confined to the pressing chamber during the pressing operation.

As the platen 2i rises, the objects supported on the plate 26 will be elevated therewith until those objects engage the under face of the intermediate plate 2i, and then continued upward movement of the platen 2! will carry with it plate 2? and the objects thereon supported, until these last mentioned objects engage the lower face of the plate The pressure on the piston 28 is then increased until the objects in the chamber A and B are subjected to the desired pressure, and this pressure is then maintained for a desired interval of time, during which the articles are heated from the plates '25, 2t and 21.

At the conclusion of this interval the pressure on the piston 26 is reduced and the platen 2i lowered. As the platen descends the intermediate plate 2? will descend until it engages the stops 29, and then the platen with its press plate 26 and the objects thereon supported, will separate from the plate 2? and will descend with the platen until the platen reaches its lower limit of movement,

as shown in the drawings. The attendants then elevate the doors or closures 5d and 83 and remove the objects from the compartments A and B, and then introduce a new set of objects to be pressed, after which the doors 5 3 and 63 are again lowered into closed positions and the pressing operation repeated.

It will be obvious that various changes in the details, which has been herein described and illustrated in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention, as expressed in the appended claims.

I claim:

1. In a hydraulic press or the like, a frame comprising apair of heavy side plates arranged side by side but spaced apart, a pair of thick head members interposed between and abutting opposite end portions of said side plates, each side plate having slots extending transversely thereof adjacent, but spaced a substantial distance from each end thereof, and each head member having a tongue extending from and along its edge face that abuts each side plate, at the corner edge of that face of that head member which is innermost, said tongue fitting said slots so as to resist separation of said head members, and means for tying the ends of said side plates to the head members at points a substantial distance outwardly from said tongues in a direction crosswise of said tongues, whereby the bending moments in the end portions of the side plates, by endwise, separating pressure between the head members, will be substantially resisted by the counter bending moments of said tie means.

2. In a hydraulic press or the like, a rectangular frame formed of a pair of thick side plates and a pair of thick head members interposed between the side plates and completing the rectangular form, the side walls of the head members which abut the side plates having integral flanges extending crosswise of the side plates and approximately at the inner faces of the head members, said side plates having grooves, in their inner faces of a size to receive and fit said flanges, and said side plates extending outwardly beyond said grooves a distance at least equal to approximately the thickness of one of said head members, and means for tying said side plates against the abutting side walls of the head members at points outwardly from said flanges at least said distance from adjacent flanges, whereby the bending moments in the end portions of the side plates by an endwise separating pressure exerted between said head members will be substantially resisted by the counter bending moments of said tie means.

3. In a hydraulic press or the like, a rectangular frame formed of a pair of thick side plates and a pair of thick head members interposed between the side plates and completing the rectangular form, the side walls of the head members which abut the side plates having integral flanges extending crosswise of the side plates and approximately at the inner faces of the head members, said side plates having grooves in their inner faces, of a size to receive and fit said flanges, and said side plates extending outwardly beyond said grooves a distance at least equal to approximately the thickness of one of said head members, a platen disposed between said side plates and having an operating stem extending through one of said head members by which said platen may be shifted toward the opposite head member, means connected to the head member through which the said stem extends through which pressure on said stem may be exerted, and tie screws connecting said side plates to said head members at points closely adjacent to the outer faces of said head members, whereby the bending moments created in the end portions of said side plates by the endwise separating pressure exerted between said head members upon a pressing movement of said platen will be substantially resisted by the counter bending moments of said tie screws.

4. In a hydraulic press or the like, a rectangular frame having spaced side plates and interposed head members, all of said members being of a substantial thickness and said head members being of materially greater thickness than said side plates, said head members having integral flanges extending entirely across the same from one open face of the frame to the other, and of substantial thickness measured in a direction lengthwise of the frame, and with the flanges beginning substantially at the inner faces of said head members, and said side plates having grooves extending transversely thereof from edge to edge, into which said flanges snugly fit, said side plates extending lengthwise of the frame, outwardly along said head members for a substantial distance, and screw studs passing through said side plates along their end edges and threaded into said head members, whereby when an endwise separating pressure is exerted between said head members, the bending moments set up in the end portions of the side plates will be substantially resisted by the counter bending moments exerted by said screws.

5. In a hydraudic press or the like, a frame formed of side members and interposed end members with opposite faces open, a platen disposed between said side members and mounted for movement from a position adjacent one of said end members toward the other end member, a hot plate secured against the inner face of said other end member, a hot plate secured to that face of the platen which is nearest said other end member, an intermediate press plate disposed between said other press plates and free to move lengthwise of said frame toward and from said other end member, means for limiting the movement of said intermediate plate in a direction away from said other end member, means for supplying heat to said press plates in all their relative positions during their movements toward and from said other end member, a heat confining screen covering each of said open faces, one of said screens having a section shiftable into an open position to expose only the chamber between said intermediate press plate and the press plate carried by said platen, when the platen and intermediate press plate are in retracted position, and the other of said screens having a section shiftable to expose only the chamber between said intermediate plate when in retracted position and the press plate which is carried by said other end member, whereby access may be provided to one of said chambers from one face of said frame, and to the other of said chambers from the other face of said frame, each of said shiftable sections being movable selectively into positions to complete closure of the face of the frame across which it extends during a pressing operation.

6. In a hydraulic press a vertical frame having side plates and end members, a platen disposed between said plates and movable in a direction between said end members, a ram associated with the lower end member and operating said platen toward and from said upper end member, a hot press plate secured to the under face of the upper end member, a hot press plate secured to the upper face of the said platen, an intermediate hot press plate disposed between said platen and upper end member, and free for movement vertically between said side plates, cooperating means between said intermediate plate and said side plates for limiting the downward movement of the said intermediate plate, upon a downward movement of said platen, to a position in which said intermediate plate is well spaced from said platen and said upper end member for creating upper and lower chambers between said hot plates, means for supplying heat to said hot plates at portions adjacent said side plates during movement of said platen carried plate and of said intermediate plate toward and from said upper end member, and a heat insulating screen covering each open face of said frame, said screens being slidable vertically into positions to close and open said chambers between the said hot plates, whereby said chambers which receive articles to be heated and pressed may be closed during pressing operations.

'7. In a hydraulic press a vertical frame having side plates and end members, a platen disposed between said plates and movable in a direction between said end members, a ram associated with the lower end member and operating said platen toward and from said upper end member, a hot press plate secured to the under face of the upper end member, a hot press plate secured to the upper face of the said platen, an intermediate hot press plate disposed between said platen and upper end member, and free for movement vertically between said side plates, cooperating means between said intermediate plate and said side plates for limiting the downward movement of the said intermediate plate, upon a downward movement of said platen, to a position in which said intermediate plate is well spaced from said platen and said upper end member for creating upper and lower chambers between said hot plates, means for supplying heat to said hot plates at portions adjacent said side plates during movement of said platen carried plate and of said intermediate plate toward and from said upper end member, a heat confining screen extending across one open face of said frame and closing both of said chambers, but having a portion shiftable vertically to provide access only to one of said chambers, a heat confining screen extending across the other open face of said frame to close the other of said chambers, and having a section shiftable vertically to permit access only to said other of said chambers, whereby access to one of said chambers is obtained from one face of said press and to the other of said chambers from the other face of said press, and both of said chambers may be closed during the pressing of articles disposed in said chambers.

8. In a hydraulic press or the like, a frame having a head at the top, and open front and rear vertical faces, a platen reciprocating vertically in said frame toward and from said head, an intermediate plate disposed between said head and platen, means for heating said platens and said head, means limiting the downward movement of said intermediate plate to a position in which it is spaced vertically from said head and said platen when said platen is in its retracted position, heat confining means closing one open face of said frame and having a portion operable to provide access only to the space between said platen and intermediate plate, and heat confining means for closing the other open face of the press and having a portion operable to provide access only to the space between said intermediate plate and said head.

9. In a hydraulic press or the like, a frame having a head at the top, and open front and rear vertical faces, a platen reciprocating vertically in said frame toward and from said head, an intermediate plate disposed between said head and platen, means limiting the downward movement of said intermediate plate to a position in which it is spaced vertically from said head and said platen when said platen is in its retracted position, heat insulating means closing one open face of said frame and having a portion operable to provide access only to the space between said platen and intermediate plate, heat insulating means closing the other open face of said frame and having a portion shiftable to provide access only to the space between said head and said intermediate plate, and steam connections to said head, said intermediate plate and said platen, disposed at the sides of said frame, for circulating steam first through said head, then downwardly and through the intermediate plate, and then through said platen to heat the same and to drain water of condensation therefrom, said connections being articulated to move with said intermediate plate and said platen during pressing operations and continuing the circulation of steam during such operations.

THOMAS F. STACY. 

